Height adjustment support for chair backs



Aug. 8, 1939. w HERQLD 2,168,620

HEIGHT ADJUSTMENT SUPPORT FOR CHAIR BACKS .Filed April6, 1957 INVENTOR \A /QLTER F HERDLD.

ATTORNEY Patented Aug. 8, 1939 UNITED STATES HEIGHT ADJUSTMENT SUPPORT FOR CHAIR BACKS Walter F. Herold, Bridgeport, Conn, assignor to The Bassick Company, Bridgeport, Conn, a corporation of Connecticut Application April 6, 1937, Serial No. 135,339

4 Claims.

The present invention relates to an improved height adjustment support for chair-backs, particularly chairs of the so-called posture type such as ofiice or typewriter chairs, and has for an 5. object to provide an adjustment support which may be easily operated by the occupant of the chair while seated therein, simply by swinging a lever by means of one of the occup-ants hands, which at the same time holds the chair-back in the adjusted position desired.

A further object is to provide adjustment means having afinger operated portion arranged upon the inner side of the back and which is adapted to have up and down movement so that the person seated in the chair may operate it by pushing down and pulling up on it, thus taking advantage of the bracing effect of his own weight seated in th chair in order to obtain relatively great pressure with little effort.

Another object is to provide adjustment means haw'ng a flat-surfaced locking portion which will not tend to loosen from side or twisting strain, as distinguished from adjustment means heretofore in use having a screw action.

Another object is to provide a support of extremely simple, economical and reliable construction and which when fixed in adjustedposition will hold the back rigidly in place without looseness.

With the above and other objects in view an embodiment of the invention is shown in the accompanying drawing and this embodiment will be hereinafter more fully described with reference thereto and the invention will be finally pointed out in. the claims.

In. the drawing:

Fig. l is a rear elevation of the adjustment chair-back support according to the illustrated exemplary embodiment of the invention.

Fig. 2 is a plan view thereof.

Fig. 3 is a vertical sectional View taken along line 3-3 of Fig. 1.

Fig. 4 is a rear elevation, partially broken away, showing the support in its released position for the purpose of allowing the back to be adjusted.

filed July 30, 1936. The corners between the side portions |0l0 and the connecting portion H of the supporting member are of beveled form, as at l2l2, the. portion H being engaged by the intermediate channel portion 13 of the lower strap member M of the chair-back, this strap member carrying at its ends the uprights l5-l5 upon the upper ends of which the upper portion of the back is secured in the usual manner. Angularly bent portions l6l6 rearwardly offset the intermediate portion l3 and engage the beveled portions l2 l2 as vertical guides which when tightly, held against the portion l2-i2 rigidly support the back against sidewise tilting movement. 7

The strap member I4 is mounted for vertical adjustment by means of a bolt ll, of the stovebolt type having a squared shoulder portion adjacent the head, and which is engaged through a circular hole l8 provided in a locking lever member 19, presently to be more fully described, a square hole 29 in the intermediate strap portion I3, and a vertical slot 2| in the portion II of the supporting member, the squared portion of the bolt being loosely engaged in the circular hole IE to permit relative swinging of the lever, and the square hole 20 and slot 2! being engaged by said square portion to hold the bolt against rotation, A washer 22 is engaged'upon the bolt, against the inner surface 'of the portion I I, and a 30 retaining nut 23 is secured thereon and locked in the desired position by a cotter pin 24.

Upon the portion I3 of the strap member there are formed, as by die-pressing, a series of radial ribs 25, preferably four in number, extending outwardly from the hole 20, the projected surfaces of these ribs being rounded. The inner end of the lever member I9 is likewise provided with die-pressed. radial ribs 26 extending outwardly from the hole l8 and which form radial grooves 40 upon the inner side, adapted in one position. of the lever to engage the ribs 25 to release the back for free vertical adjustment movement, as shown in Fig. 4, and in the other position to be out of engagement, the flat inner surface of the lever engaging the ribs in this position, and the rounded surfaces of the ribs serving as camming means to effect a tight wedging engagement of the lever between the nut head and the strap member, which securely holds the chair-back in its adjusted position. Because of the arrangement of the flat wedging surface side or twisting strains upon the back will not tend to loosen the lever member.

The lever member is of such length that it may be operated with comparative ease by the fingers and at the same time the wedging action which occurs close to the pivot axis is extremely tight.

The end of the lever is provided with a finger engaging end 2'! bent into U-shape to engage about the lower edge of the strap member in the locked position, and having a horizontally bent end 28 at the inner side of the strap member, and which is close enough to one side of the back that one hand of the occupant of the chair may operate the lever with a finger either to release or lock it while still holding the back. In this way the back may be exactly adjusted to the position desired and accurately locked in this position. As the finger member has an up and down movement the person operating it will obtain the pressure advantage from the bracing effect of his own weight seated in the chair.

I have illustrated and described a preferred and satisfactory embodiment of the invention, but it will be understood that changes may bemade therein, within the spirit and scope thereof, as defined in the appended claims.

Having herein described my invention what I claim and desire to secure by Letters Patent is 1. In an adjustment support for a chair-back, a. supporting member, a chair-back carrying member having a transversely extending lower end portion, mounted for relative vertical adjustm-ent movement on said supporting member, and releasing and locking means relatively rotatable about a substantially horizontal axis substantially at right angles to the plane of vertical adjustment of said chair back member and comprising wedging means cooperating between said supporting member and said chair-back member, and actuating means therefor consisting of a lever arm disposed rearwardly of said lower end portion of said chair-back member extending from said wedging means into proximity to one side of said chair-back member and arranged to have up and down swinging movement in a plane substantially parallel to the plane of vertical adjustment of said chair-back memberto actuate said wedging means, and a finger engaging part rigidly connected to said arm and extending from said arm to the forward side of said chair-back member.

2. In an adjustment support for a chair-back, a supporting member, a chair-back carrying member, one of said members having a slot, a bolt carried by the other member and engaged with said slot, abutment means on said bolt, a locking lever member disposed about said bolt between said abutment means and one of said members, radially disposed camming means carried by said one member, and radially disposed camming means carried by said lever member, there being flat surfaces on one of said last two mentioned members between said camming means, said camming means of said one member and said lever member adapted to register in one operative position and the camming means of one of said members adapted to engage the fiat surface of the other member in the other operative position.

3. In an adjustment support for a chair-back, a supporting member, a. chair-back carrying member, one of said members having a slot, a bolt carried by the other member and engaged with said slot, abutment means on said bolt, a locking lever member disposed about said bolt between said abutment means and one of said members, radially disposed camming projections on said one member, and radially disposed camming recesses on said lever member, there being flat surfaces on said lever member between said recesses, said projections and recesses adapted to register in one operative position and said flat surfaces adapted to engage said projections in the other operative position.

4. In an adjustment support for a chair back, a supporting member, a chair back carrying member, one of said members having a slot, a bolt carried by the other member and engaged with said slot, abutment means on said bolt, a locking lever member disposed about said bolt between said abutment means and one of said members, locking means associated with said one member having camming projection means, locking means associated with said lever member having camming recess means, there being a wedging surface on said lever member adjacent said recess means, said projection means and recess means adapted to register in one operative position and said wedge surface adapted to engage said projection means in the other operative position.

WALTER F. HEROLD. 

